<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>getElementsByTagName</title>
    </head>
    <body>
        <ul>
            <li>Coffee</li>
            <li>Tea</li>
        </ul>

        <p id="demo">单击“按钮”更改列表项的文本。</p>
        <button onclick="myFunction()">点我</button>

        <script src="getElementsByTagName.js"></script>
    </body>
</html>